Western Riverside County Multiple Species Habitat Conservation Plan Biological Monitoring Program 2016 Delhi Sands Flower-loving Fly (Rhaphiomidas terminatus abdominalis) Survey Report 27 September 2017 2016 Delhi Sands Flower-loving Fly Survey Report TABLE OF CONTENTS INTRODUCTION .................................................................................................................... 1 SURVEY GOALS AND OBJECTIVES ...................................................................................................... 1 METHODS ............................................................................................................................ 2 PROTOCOL DEVELOPMENT ................................................................................................................ 2 TRAINING ........................................................................................................................................... 2 STUDY SITE SELECTION AND TRANSECT PLACEMENT ....................................................................... 3 SURVEY METHODS ............................................................................................................................ 3 DATA ANALYSIS ................................................................................................................................ 6 RESULTS .............................................................................................................................. 7 LINE-TRANSECT SURVEYS ................................................................................................................. 7 VEGETATION SAMPLING .................................................................................................................... 9 DISCUSSION ....................................................................................................................... 13 RECOMMENDATIONS ........................................................................................................................ 15 ACKNOWLEDGEMENTS ....................................................................................................... 15 REFERENCES ...................................................................................................................... 16 LIST OF TABLES Table 1. Most common plant species and families recorded across 300 resampled vegetation plots and 38 exuviae plots in 2016. ................................................................. 10 Table 2. Comparisons between average ground cover percentages, average vegetation class cover percentages, and soil compactness across sites sampled during 2008-2016. 11 Table 3. Results of paired t-test comparisons between target species/family mean percent coverage across 300 vegetation sampling plots in 2010 and 2016. .................................. 12 Table 4. Results of paired t-test comparisons between target species/family percent coverage across 300 vegetation sampling plots in 2015 and 2016. .................................. 12 Table 5. Results of Welch two sample t-test comparisons between target species/family percent coverage across 300 resampled vegetation sampling plots and 38 exuviae plots in 2016................................................................................................................................... 13 LIST OF FIGURES Figure 1. Vegetation sampling plots at Teledyne in 2016 ................................................. 5 Figure 2. Delhi Sands flower-loving fly detections at Teledyne in 2016 .......................... 8 Figure 3. Delhi Sands flower-loving fly observations per km surveyed and annual density estimates (individuals per ha) from 2005-2016. ................................................... 14 Western Riverside County MSHCP ii Biological Monitoring Program 2016 Delhi Sands Flower-loving Fly Survey Report NOTE TO READER: This report is an account of survey activities conducted by the Biological Monitoring Program for the Western Riverside County Multiple Species Habitat Conservation Plan (MSHCP). The MSHCP was permitted in June 2004. Reserve assembly is ongoing and is expected to take 20 or more years to complete. The Conservation Area includes lands acquired under the terms of the MSHCP and other lands that have conservation value in the Plan Area (called public or quasi-public lands in the MSHCP). In this report, the term “Conservation Area” refers to these lands as they were understood by the Monitoring Program at the time the surveys were conducted. The Monitoring Program monitors the status and distribution of the 146 species covered by the MSHCP within the Conservation Area to provide information to Permittees, land managers, the public, and the Wildlife Agencies [i.e., the California Department of Fish and Wildlife (CDFW, formerly California Department of Fish and Game) and the U.S. Fish and Wildlife Service]. Monitoring Program activities are guided by defined conservation objectives for each Covered Species, other information needs identified in MSHCP Section 5.3 or elsewhere in the document, and the information needs of the Permittees. A list of the lands where data collection activities were conducted in 2016 is included in Section 7.0 of the Western Riverside County Regional Conservation Authority (RCA) Annual Report to the Wildlife Agencies. The primary author of this report was the 2016 Delhi Sands flower-loving fly Project Lead, Tara Graham. This report should be cited as: Biological Monitoring Program. 2017. Western Riverside County MSHCP Biological Monitoring Program 2016 Delhi Sands Flower-loving Fly Survey Report. Prepared for the Western Riverside County Multiple Species Habitat Conservation Plan. Riverside, CA. Available online: http://wrc-rca.org/about-rca/monitoring/monitoring-surveys/. While we have made every effort to accurately represent our data and results, it should be recognized that data management and analysis are ongoing activities. Any reader wishing to make further use of the information or data provided in this report should contact the Monitoring Program to ensure that they have access to the best available or most current data. Please contact the Monitoring Program Administrator with questions about the information provided in this report. Questions about the MSHCP should be directed to the Executive Director of the RCA. Further information on the MSHCP and the RCA can be found at www.wrc-rca.org. Contact Information: Executive Director Monitoring Program Administrator Western Riverside County Western Riverside County MSHCP Regional Conservation Authority Biological Monitoring Program Riverside Centre Building 4500 Glenwood Drive, Bldg. C 3403 10th Street, Suite 320 Riverside, CA 92501 Riverside, CA 92501 Ph: (951) 248-2552 Ph: (951) 955-9700 Western Riverside County MSHCP iii Biological Monitoring Program 2016 Delhi Sands Flower-loving Fly Survey Report INTRODUCTION The Delhi Sands flower-loving fly (Rhaphiomidas terminatus abdominalis; Delhi fly) is federally listed as endangered, and is narrowly distributed in portions of Riverside and San Bernardino Counties in areas with Delhi series soils. The species is known to have occurred within 3 Core Areas defined by the Western Riverside County Multiple Species Habitat Conservation Plan (MSHCP): Jurupa Hills, Agua Mansa Industrial Center, and Mira Loma (Dudek & Associates 2003). To date, conservation of the species within the MSHCP Plan Area has only occurred at the Teledyne site within the Jurupa Hills Core Area. There are no lands that are currently part of the Conservation Area within the other 2 Core Areas for this species; however, the Rivers and Lands Conservancy has been actively procuring lands in San Bernardino County in those general areas for Delhi fly conservation. Delhi fly Conservation Objective 2 states that successful reproduction shall be documented at all Core Areas once a year for the first 5 years after permit issuance and then as appropriate, but not less frequently than every 8 years thereafter (Dudek & Associates 2003). Reproductive success is defined in the MSHCP as the presence of pupal cases (exuviae) or newly-emerged (teneral) individuals. Because Delhi fly is an endangered species with an extremely limited distribution within the Plan Area, Monitoring Program biologists have surveyed for Delhi fly within the lone accessible Core Area annually since 2005. We describe here the procedure and results of the MSHCP Biological Monitoring Program’s 2016 effort to monitor Delhi fly in the Jurupa Hills. Delhi Sands flower-loving fly has distinctive biological and habitat requirements and faces a number of threats (USFWS 1997). The life cycle of the fly includes egg, larval, pupal, and adult stages. Only the adult stage occurs above-ground, when adults emerge to breed during the summer months. The species is restricted to fine, sandy Delhi series soils, usually with wholly- or partly-stabilized sand dunes and sparse native vegetation. Areas with suitable fly habitat have been highly affected by anthropogenic activities, including conversion to agriculture, residential and commercial development, surface mining for sand, dumping of trash and cow manure, and damage by off-road vehicles. Invasive exotic plants are also thought to degrade fly habitat by increasing vegetation cover or by altering soil conditions through dune stabilization and changes in soil moisture. The MSHCP Management Program began management actions on-site in 2010 to increase habitat suitability by controlling the spread